This invention relates to a computer mouse assembly including a protective cover.
A computer mouse is widely used as a pointing device for a personal computer, for controlling movement of a cursor over the display screen of the computer's monitor. The common form of computer mouse has a mouse body for gripping in the user's hand, the mouse body having a bottom wall which slides over a mouse pad. The bottom wall of the mouse body is formed with an opening which affords access to a cavity containing a mouse ball and a movement encoding mechanism. A retainer plate formed with a circular hole is fitted removably in the opening in the bottom wall of the mouse body. The diameter of the circular hole in the retainer plate is somewhat smaller than the diameter of the mouse ball, so the mouse ball is held captive in the cavity in the mouse body but protrudes through the hole in the retainer plate. As the user slides the mouse over the mouse pad, the mouse ball rolls against the movement encoding mechanism, which detects the rolling movement of the mouse ball and generates an electrical pulse signal in response thereto. The pulse signal is supplied to the computer's system unit and is used by the system unit to control movement of the cursor over the computer's monitor screen.
The computers that are used in schools are frequently equipped with mouses. If foreign matter is present on the mouse pad, it might be carried by the mouse ball into the cavity of the mouse body, where it is transferred to the movement encoding mechanism and there is a possibility that operation of the movement encoding mechanism will be impaired. This may lead to erratic movement of the cursor. Although efforts are made to keep school computer labs clean, the computer mouse is frequently in need of cleaning to remove dirt from the ball and from the movement encoding mechanism. Moreover, there is a continuing problem in school computer labs of students removing mouse balls, requiring that the balls be replaced or that the entire mouse be replaced.
The typical mouse pad is rectangular and is about 10 inches by about 8 inches. Nevertheless, it is commonly necessary to move the mouse less than two inches in order to displace the cursor from left to right of the monitor and by less than one inch to displace the cursor from top to bottom of the monitor. Thus, it is not normally necessary to be able to move the mouse continuously, in a single sweep, from side to side or forward and back over the whole extent of the mouse pad.